The present disclosure relates to diffusion sheets, backlight units, and liquid crystal display devices. Recently, liquid crystal display devices have been widely used as flat panel displays. Such liquid crystal display devices include a liquid crystal display panel in which a liquid crystal layer is sealed between a thin film transistor (TFT) substrate and a color filter (CF) substrate, and a backlight unit provided to a back surface of the liquid crystal display panel. For example, the backlight unit includes a rectangular-shaped light guide plate, a plurality of light sources provided along one side surface of the light guide plate, a diffusion sheet and a prism sheet which are sequentially provided on the front surface of the light guide plate, and a reflection sheet provided on the back surface of the light guide plate.
For example, Japanese Unexamined Patent Publication No. 2012-226290 discloses a diffusion sheet having a plurality of grooves on at least one surface thereof, the grooves being randomly arranged in parallel to each other.